Electric alarm



(No Model.)

ELECTRIC ALARM. No. 486,338. Patented Nov. 15, 1892.

WITNESSES: lNVENTOH LZZ iii-"J 21W ATTORNEYS,

UNITED STATES PATENT OFFIC HENRY A. HULL, OF NEW BRUNSWICK, NEW JERSEY.

ELECTRIC ALARM.

SPECIFICATION forming-part of Letters Patent No. 486,338, dated Ncvember15, 1892.

Application filed April 20, 1892. Serial No. 429,871- (No model.)

To all whom it may concern:

Be itknown that I, HENRY A. HULL, of New Brunswick, in the county ofMiddlesex and State of New Jersey, have invented a new and ImprovedElectric Alarm, of which the following is a full, clear, and exactdescription.

The object of the invention is to provide a new and improved electricalarm which is simple and durable in construction and more especiallydesigned for use on doors to give an alarm for a certain length of timeonly on the opening of the door, thus preventing the continuous soundingof the alarm as long as the door is open and remains open, as is thecase in electrical alarms of this class now constructed.

The invention consists of a rod or button having'a contact-point adaptedto pass successively over the opposite faces of a contactspring, one ofthe faces being insulated.

The invention also consists of certain parts and details andcombinations of the same, as will be hereinafter described, and thenpointed out in the claims.

Reference is to be had to the accompanying drawings, forming a part ofthis specification, in which similar letters of reference indicatecorresponding parts in all the figures.

Figure 1 is aplan view of the improvement as arranged for and applied toa door. Fig. 2 is a side elevation of the improvement with parts insection. Fig. 3 is a rear elevation of the same, and Fig. 4 is asectional plan view of the improvement on the line 4 4 of Fig. 2.

The improved electric alarm is provided with a plate A, from whichprojects rearward a frame B, adapted to be let into the doorjamb O, asplainly shown in Fig. 1. In the rear end of the frame B and in the plateA is mounted to slide and to turn arod or button D, on the rear reducedend of which is coiled a springE, pressing with one end on the frame Band with its other end on the shoulder formed by the reduced end of therod D. The spring E serves to hold the outer enlarged end of the buttonD in an outermost position, so that the button projects from the face ofthe plate A and is adapted to be engaged by the door C when thelatter isclosed. In closing the door the rod or button D. is pressed rearward, soas to compress the spring E,

and when the door is opened the compressed spring returns the button orrod D to its normal'position. (Shown in Figs. 1 and 2.) From the rod orbutton D extends a pin F,passing is pressed rearward, it is turned toone side by the pin F, traveling in the slot B, and on the returnmovement of the said rod or button it is turned in the oppositedirection back to its former position, as shown in Fig. 4.

The upper projecting end of the pin F is adapted to pass over the twofaces G and G of a contact-spring G,secured on a flange H, projectingfrom a ring H, insulated from the plate A. The flange H of the saidinsulated ring H is connected with a wire I, leading to the alarm J ofthe usual construction, and the said alarm is connected by a wire I withthe battery K, connected by the wire I with the frame B or the plate A,so as to complete the circuit, as hereinafter more fully described.

When the button D is in an outermost position, as shown in Figs. 1, 2,and 4:, then the pin F is in front of the contact-spring G, and when thedoor is closed and the button or rod is pressed rearward then thecontact-pin F, traveling in the slot B, passes over the insulated face Gof the contact-spring G, the said spring being bent to one side untilthe pin has passed into the rear end of the slot 13'. On the returnmovement of the button D-that is, when the door 0 is openedthe pin Fengages the other face G of the contact-spring G and remains in contactwith the latter until it passes over the front edge of the said face Gto finally disengage the contact-spring entirely on the final completeoutward movement of the button or rod D. Now it will be seen that whenthe door 0 is closed then the pin F is in the rear end of the slot Bthat is, out of contact with the contact-spring G. Now when the door isopened the spring E moves the rod or button D outward, so that thecontactpin F passes onto the face G of the contactspring G, whereby thecircuit is completed and the alarm J is sounded. The alarm sounds aslong as the pin F is in contact with the face G of the contact-springG-that is, until the door 0 has been opened far enough to finallydisengage the outer end of the rod or button D. When this latter takesplace, the spring E moves the rod or button into an outermost position,so that the pinF is disengaged from the contact-spring, and the alarmthen ceases.

In closing the door the rod or button D is pushed rearward and the pin Ftravels over the insulated face G of the contact-spring G, so that noalarm is sounded on the closing of the door. At the same time the buttonor rod D is turned by the pin F traveling into the rearmost end of theslot B, so that when the door is again opened the pin passes over theface G of the contact-spring G to again sound the alarm for a certainlength of timethat is, as long as the pin passes over the said face GHaving thus fully described my invention, I claim as new and desire tosecure by Letters Patent-- 1. In an electric alarm, the combination,with a contactspring having two faces, one of which is insulated, of arod which is provided with a pin and adapted to slide, whereby when therod reciprocates the said pin passes in contact with one side and thenthe other side of said spring, as shown and described, for the purposespecified.

2. An electric alarm provided with a rod mounted to slide and to turnand carrying a oontact pin and a contact-spring provided on its free endwith two faces, of which one is insulated, and both faces adapted to bealter nately engaged by the said contact-pin, as set forth.

3. In an electric alarm, the combination, with a spring-pressed rod orbutton mounted to turn and to slide and a contact-pin arranged on thesaid rod or button, of a contact-spring formed at its free end with twofaces, of which one is insulated, the faces ex tending in the path ofthe said pin in such a manner that when the rod is pressed the pinpasses over theinsulated face and when the pressure is released the pinpasses over the other face, substantially as shown and described.

4.. In an electric alarm, the combination, with a plate supportingaframe and connected with a battery, of a spring-pressed rod or buttonfitted to slide in the said plate and frame, a pin held on the said rodor button, a contact-spring insulated on the said plate and connectedwith the alarm and the other pole of the battery, the saidcontact-spring being formed with two faces, of which one is insulated,and both adapted to be alternately engaged by the pin on the pressingand releasing of the said button, substantially as shown and described.

HENRY A. HULL. Witnesses:

W. EDWIN FLORANCE, J. B. KIRKPATRICK.

